activity
20132026
most citedPolarized Blazar X-rays imply particle acceleration in shocks

140 citations · 2k across the 60 of their papers we have counts for

collaborators

61 papers

astro-ph.IM2026

WALOP-South: a four camera one shot imaging polarimeter for the PASIPHAE survey. Paper III -- PSF modelling

Indrajit Paul, Kishan Deka, Tuhin Ghosh +22

The two WALOP instruments, built for the PASIPHAE survey, will measure the linear polarization of large numbers of stars in the Galactic polar regions in the SDSS- band. They ar…

astro-ph.GA2026

3D Magnetic Field Vectors in Space: Bubbles, Clouds, and Filaments

Mehrnoosh Tahani, Anna Ordog, Jennifer West +3

Magnetic fields play important roles in the star-formation process across different spatial scales. The interplay between magnetic field strength (a key component of the interstell…

astro-ph.GA2026

Small-scale Magnetic Fields in the Milky Way and Nearby Galaxies

Yik Ki Ma, Amit Seta, Aritra Basu +13

Magnetic fields in galaxies span decades in physical scale, from the coherent magnetic fields on galactic scales (> kpc) to the random magnetic fields from 100 pc to the resistive…

astro-ph.GA2026

SIMPLIFI-Study of Interstellar Magnetic Polarization: A Legacy Investigation of Filaments. II. Enhancement of grain alignment near embedded protostars in the DR21 Ridge

S. Kumar, T. G. S. Pillai, G. V. Panopoulou +10

Thermal dust continuum polarimetry is a powerful indirect probe of magnetic field geometry in dense molecular clouds while at the same time providing information on the alignment o…

astro-ph.GA2025

Evidence for cloud-to-cloud variations in the ratio of polarized thermal dust emission to starlight polarization

Nidhi Mehandiratta, Georgia V. Panopoulou, Eirik Gjerløw +12

The correlation between optical starlight polarization and polarized thermal dust emission can be used to infer intrinsic dust properties. This correlation is quantified by the rat…

astro-ph.IM2025

Wide Area Linear Optical Polarimeter Control Software

John A. Kypriotakis, Bhushan Joshi, Dmitry Blinov +19

The WALOPControl software is designed to facilitate comprehensive control and operation of the WALOP (Wide Area Linear Optical Polarimeter) polarimeters, ensuring safe and concurre…

astro-ph.HE2025

IXPE Observations of the Blazar Mrk 501 in 2022: A Multiwavelength View

L. Lisalda, E. Gau, H. Krawczynski +157

The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and 2022 July with the Imaging X-ray Polarimetry Explorer (IXPE). In thi…

astro-ph.SR2025

Analyzing Stellar and Interstellar Contributions to Polarization: Modeling Approaches for Hot Stars

R Ignace, A G Fullard, G V Panopoulou +3

Linear polarimetry of unresolved stars is a powerful method for discerning or constraining the geometry of a source and its environment, since spherical sources produce no net pola…

astro-ph.IM2024★ 2 cited

The WALOP-North Instrument I: Optical Design, Filter Design, Calibration

John A. Kypriotakis, Siddharth Maharana, Ramya M. Anche +18

The Wide Area Linear Optical Polarimeter North (WALOP-North) is an optical polarimeter designed for the needs of the PASIPHAE survey. It will be installed on the 1.3m telescope at…

astro-ph.IM2024

Systems design, assembly, integration and lab testing of WALOP-South Polarimeter

Siddharth Maharana, A. N. Ramaprakash, Chaitanya Rajarshi +28

Wide-Area Linear Optical Polarimeter (WALOP)-South is the first wide-field and survey-capacity polarimeter in the optical wavelengths. On schedule for commissioning in 2024, it wil…

astro-ph.GA2024★ 6 cited

The magnetic field of the Radcliffe Wave: starlight polarization at nearest approach to the Sun

G. V. Panopoulou, C. Zucker, D. Clemens +6

We investigate the geometry of the magnetic field towards the Radcliffe Wave, a coherent 3-kpc-long part of the nearby Local Arm recently discovered via three-dimensional dust mapp…

astro-ph.GA2024★ 23 cited

The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium

V. Pelgrims, N. Mandarakas, R. Skalidis +21

We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimet…

astro-ph.SR2023

Zero-polarization candidate regions for calibration of wide-field optical polarimeters

N. Mandarakas, G. V. Panopoulou, V. Pelgrims +14

Context. Calibration of optical polarimeters relies on the use of stars with negligible polarization (unpolarized standard stars) for determining the instrumental polarization zero…

astro-ph.HE2023★ 2 cited

Observations of Low and Intermediate Spectral Peak Blazars with the Imaging X-ray Polarimetry Explorer

Herman L. Marshall, Ioannis Liodakis, Alan P. Marscher +145

We present X-ray polarimetry observations from the Imaging X-ray Polarimetry Explorer (IXPE) of three low spectral peak and one intermediate spectral peak blazars, namely 3C 273, 3…

astro-ph.GA2023★ 2 cited

Synchrotron Signatures of Cosmic Ray Transport Physics in Galaxies

Sam B. Ponnada, Iryna S. Butsky, Raphael Skalidis +7

Cosmic rays (CRs) may drive outflows and alter the phase structure of the circumgalactic medium, with potentially important implications on galaxy formation. However, these effects…

astro-ph.GA2023★ 19 cited

Synchrotron Emission on FIRE: Equipartition Estimators of Magnetic Fields in Simulated Galaxies with Spectrally-Resolved Cosmic Rays

Sam B. Ponnada, Georgia V. Panopoulou, Iryna S. Butsky +7

Synchrotron emission is one of few observable tracers of galactic magnetic fields (\textbf{B}) and cosmic rays (CRs). Much of our understanding of \textbf{B} in galaxies comes from…

astro-ph.IM2023★ 12 cited

The RoboPol sample of optical polarimetric standards

D. Blinov, S. Maharana, F. Bouzelou +34

Optical polarimeters are typically calibrated using measurements of stars with known and stable polarization parameters. However, there is a lack of such stars available across the…

astro-ph.GA2023★ 1 cited

A compilation of optical starlight polarization catalogs

G. V. Panopoulou, L. Markopoulioti, F. Bouzelou +7

Polarimetry of stars at optical and near-infrared wavelengths is an invaluable tool for tracing interstellar dust and magnetic fields. Recent studies have demonstrated the power of…

astro-ph.SR2023★ 1 cited

IRAS 00450+7401 and the mid-infrared fade/burst cycle of R Coronae Borealis-type stars

William A. Burris, Carl Melis, Allen W. Shafter +3

We present optical and infrared imaging and spectroscopy of the R Coronae Borealis-type (R Cor Bor) star IRAS 00450+7401. Optical spectra further confirm its classification as a co…

astro-ph.IM2023★ 4 cited

Bright-Moon Sky as a Wide-Field Linear Polarimetric Flat Source for Calibration

S. Maharana, S. Kiehlmann, D. Blinov +20

Next-generation wide-field optical polarimeters like the Wide-Area Linear Optical Polarimeters (WALOPs) have a field of view (FoV) of tens of arcminutes. For efficient and accurate…

astro-ph.GA2023★ 7 cited

CO enhancement by magnetohydrodynamic waves; Striations in the Polaris Flare

R. Skalidis, K. Gkimisi, K. Tassis +4

The formation of molecular gas in interstellar clouds is a slow process, but is enhanced by gas compression. Magnetohydrodynamic (MHD) waves create compressed quasiperiodic linear…

astro-ph.HE2022★ 44 cited

X-ray Polarization Observations of BL Lacertae

Riccardo Middei, Ioannis Liodakis, Matteo Perri +143

Blazars are a class of jet-dominated active galactic nuclei with a typical double-humped spectral energy distribution. It is of common consensus the Synchrotron emission to be resp…

astro-ph.HE2022★ 140 cited

Polarized Blazar X-rays imply particle acceleration in shocks

Ioannis Liodakis, Alan P. Marscher, Iván Agudo +125

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to $\sim 1…

astro-ph.IM2022★ 6 cited

WALOP-South: A Four-Camera One-Shot Imaging Polarimeter for PASIPHAE Survey. Paper II -- Polarimetric Modelling and Calibration

Siddharth Maharana, Ramya M. Anche, A. N. Ramaprakash +22

The Wide-Area Linear Optical Polarimeter (WALOP)-South instrument is an upcoming wide-field and high-accuracy optical polarimeter to be used as a survey instrument for carrying out…